We report on users ’ revisitation patterns to World Wide Web (web) pages, and use the results to lay an empirical foundation for the design of history mechanisms in web browsers. Through history, a user can return quickly to a previously visited page, possibly reducing the cognitive and physical overhead required to navigate to it from scratch. We analysed 6 weeks of detailed usage data collected from 23 users of a wellknown web browser. We found that 58 % of an individual’s pages are revisits, and that users continually add new web pages into their repertoire of visited pages. People tend to revisit pages just visited, access only a few pages frequently, browse in very small clusters of related pages and generate only short sequences of repeated URL paths. We compared different history mechanisms, and found that the stack-based prediction method prevalent in commercial browsers is inferior to the simpler approach of showing the last few recently visited URLs with duplicates removed. Other predictive approaches fare even better. Based on empirical evidence, eight design guidelines for web browser history mechanisms were then formulated. When used to evaluate the existing hypertext-based history mechanisms, they explain why some aspects of today’s browsers seem to work well, and other’s poorly. The guidelines also indicate how history mechanisms in the web can be made even more effective. † � 1997 Academic Press Limited 1.

A user interface software tool helps developers design and implement the user interface. Research on past tools has had enormous impact on today's developers---virtually all applications today were built using some form of user interface tool. In this paper, we consider cases of both success and failure in past user interface tools. From these cases we extract a set of themes which can serve as lessons for future work. Using these themes, past tools can be characterized by what aspects of the user interface they addressed, their threshold and ceiling, what path of least resistance they offer, how predictable they are to use, and whether they addressed a target that became irrelevant. We believe the lessons of these past themes are particularly important now, because increasingly rapid technological changes are likely to significantly change user interfaces. We are at the dawn of an era where user interfaces are about to break out of the "desktop" box where they have been stuck for the ...

We report on a field study about how software developers experience disorientation when using the Eclipse Java integrated development environment. We analyzed the data using the theory of visual momentum, identifying three factors that may lead to disorientation: the absence of connecting navigation context during program exploration, thrashing between displays to view necessary pieces of code, and the pursuit of sometimes unrelated subtasks. 1.

Current state--of--the--art graphics workstations allow us to create images in less than 100 ms which are almost photorealistic; some can even render two images in the same amount of time for stereoscopic viewing. The development of new input devices, interaction techniques and interaction metaphors which can exploit the power of these workstations is, however, in its infancy. Virtual reality makes use of these capabilities in order to give the user the sensation of being part of an environment in which they are able to manipulate virtual objects directly. But, in our opinion, the successful use of virtual reality in industrial applications depends critically upon the quality of interaction which can be achieved between this new technology and the users "within" it. If this match is not achieved then the technology cannot hope to realise its full potential. This paper presents a classification for levels of interaction for 2D and 3D graphics in order to show how far the development of ...

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The Zoom Browser is a novel Hypertext Markup Language (HTML) browser for the World Wide Web (WWW). Utilizing a new focus+context visualization technique, called flip zooming, the Zoom Browser is capable of giving a focus+context view of large documents and of displaying multiple HTML documents simultaneously. Compared to traditional methods for navigating large documents, such as scroll bars, flip zooming offers advantages such as giving a contextual overview and allowing instant access to any part in a document. It also offers advantages over previous focus+context methods for presenting large documents, including less deformation of text and improved real-time performance. The Zoom Browser is written in Java which allows easy integration with other WWW-based applications.

The window manager, a program which helps users organize and access their computers ’ open windows, is central to many aspects of computer work. Research in window managers has recently aimed to leverage users ’ tasks to organize the growing number of open windows in a useful manner. This research has assumed task classifications to be binary – a window is in a task, or not – and context-independent. However, our fieldwork and background theory suggest that neither is necessarily the case. Instead, we focus on association as an organizational scheme – windows can associate with tasks to varying degrees. We then introduce Taskposé, a prototype system that capitalizes on this idea through a full-screen graphical interface, and report on a weeklong user study. Finally, we comment on future directions for the prototype.

window management